Domain Prefix

Hey!

I have my NAS set up so that prefix.domain.com points towards the DSM. This works perfectly so that I do not have to use domain.com:5001.

My one issue is that both shared links that I send and the reports I get emailed default to https://prefix.domain.com:5001/sharing/asdfasdf I have to manually remove the ":5001" which both defeats the point of using my prefix and is annoying.

Am I missing a setting? to make this work properly?

Thanks!

p.s. Please not that I have this set up on my DiskStation and not just using forwarding. Application portal works fine and https://prefix.domain.com/sharing/asdfasdf works when I remove the port. Just that something in the system thinks it needs to add that.